Evaluation of aircraft wheel and brake temperatures based on infrared thermographic imaging

Aircraft wheels and brakes are safety critical systems which play a critical role in supporting aircraft ground operations, specifically during the aircraft deceleration phase. The energy absorbed by the wheels and brakes has a significant impact on the nitrogen pressure within the tyre, which can potentially impact the tyre performance. This could lead to: unscheduled maintenance on wheels and brakes, and/or fuel inefficiency, and/or increase in overall maintenance costs, and/or accidents during ground operation. The existing single aisle commercial aircraft have insufficient instrumentation on wheels and brakes and therefore provide limited technical data to support the understanding of wheel and brake temperatures and their interdependencies with the external environment. In this paper an innovative approach has been proposed, and demonstrated, to capture the temperature signatures of various critical locations on the aircraft wheels and brakes based on the use of an infrared thermographic camera. To support the overall implementation of this research study, the Cranfield University National Flying Laboratory Centre (NFLC) Saab 340B (Registration number G-NFLB) aircraft has been investigated. The wheel and brake temperature signatures have been acquired corresponding to two different flight profiles. The acquired results suggest that the employed thermographic camera can consistently capture temperature trends at all target locations across both flight profiles. Furthermore, trends detected at each location provide engineering insight into the cooling pattern corresponding to each location, including the influence of the external environment. The results therefore pave the scientific foundation to further develop the engineering understanding of the wheel and brake temperature data set that can be utilised in supporting the implementation of a condition monitoring solution for accurate prediction of tyre pressure.